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Our Place in the Cosmos: The Unfinished Revolution by Fred Hoyle and
Chandra Wickramasinghe, J. M. Dent, pp 190, £16.99

Some years ago the Royal Astronomical Society hosted a symposium to examine
the claims of Fred Hoyle and Chandra Wickramasinghe, the authors of Our
Place in the Cosmos, that life could have arisen in interstellar space.
Hoyle and Wickramasinghe presented a paper in which they claimed to have
detected an amino acid, tryptophan, along the line of sight to a star. A
bump in an ultraviolet absorption spectrum corresponded so faithfully to the
spectral signature of tryptophan that such a match could surely not have
happened by chance.

Fortunately someone in the audience knew better. He pointed out that the
data, archive material obtained by the IUE satellite, had been wrongly
calibrated. The apparent absorption feature was caused by the strong signal
from the star used to calibrate the detector which had saturated it. It is
an effect well known to those who work with IUE data. If the spectrum had
been properly calibrated the bump would have disappeared and so would
interstellar tryptophan. Hoyle and Wickramasinghe were gobsmacked.

A decade later the thesis of this book, which the authors bravely claim to
be ‘irrefutable’, remains profound if no longer novel. Life arose not in
Charles Darwin’s ‘warm little pond’, but in the cold depths of space.
Interstellar dust is made of viruses and freeze-dried bacteria that are
borne to the inner Solar System on comets. These evaporate in the heat of
the Sun and release the organisms, which are swept up by the Earth and
eventually find their way to the ground. The Earth was first seeded with
life about 3 billion years ago and the seeding continues to this day. Every
year 1021 bacteria and perhaps 1025 viruses drop into the atmosphere, where
they cause diseases such as influenza, whooping cough, measles, infective
jaundice, viral meningitis, legionnaire’s disease and bubonic plague.

Evolution, claim Hoyle and Wickramasinghe, proceeds not by the cumulative
random mutations of genes, but in bursts of activity stimulated by the
arrival of new genes from the sky. A single event 570 million years ago,
perhaps the collision of a broken comet, deposited a swarm of organisms
including not only viruses and bacteria, but also the frozen eggs of
primitive animals. Thus was delivered most of the genetic information that
now characterises life on Earth. Subsequent evolution has been a matter of
the genes unscrambling and finding new homes, with the continued assistance
of infalling viruses.

Hoyle and Wickramasinghe have been advocating notions along these lines for
a good many years (foreshadowed by Hoyle’s 1957 novel The Black Cloud, which
told of an encounter with an intelligence residing within an interstellar
dust cloud). Part of the evidence cited in this book is the profusion of
organic molecules in space; similarities between the infrared absorption
spectra of interstellar dust and those of bacteria; the ‘unearthly
properties’ of certain bacteria, such as their resistance to radiation and
to extremes of temperature and pressure, that show they did not evolve on
Earth; and patterns of infectious disease that indicate that the bugs could
not have diffused through the population but must have fallen from the sky.
(Whooping cough, for instance, comes from Encke’s comet.)

Such radical propositions are bound to attract criticism and Hoyle and
Wickramasinghe do not accept criticism gracefully. They heap scorn on those
who might doubt their views. There is much dark talk of ‘dogma’ and
‘propaganda’, with unpleasant swipes at the ‘deceits’ and ‘tricks’ of fellow
scientists, especially those whose only offence is to be biologists. The
view that carbon-based molecules in space may have a nonbiological origin
is ‘to carry dogma to extreme lengths’, while the theory of evolution is ‘a
sustained campaign of propaganda on the part of biologists’. And the lack
of fossil evidence for a primal ancestor to life on Earth is ‘yet another
blow to Earth-centred Darwinists . . . another blow to add to all the others
that rain down on their heads, a rain which will increase relentlessly in
its intensity until their position eventually disintegrates’. I’ve seen this
sort of stuff in books about flying saucers and Bermuda triangles. It does
not enhance the authors’ credibility.

Biologists may well feel differently, but the attitude of astronomers to
these ideas is generally one of bemused tolerance, tinged with sadness that
a scientist of Sir Fred’s calibre should be devoting his talents to a
seemingly hopeless cause. Any hostility surely stems from frustration with a
pair of theorists who, by snubbing the wisdom of colleagues while dabbling
in experimental fields outside their competence, can make an elementary
blunder and proclaim it to be an amino acid.

Polemic aside, what of the science? The Royal Astronomical Society’s
symposium proceeded in a genteel haze towards the only conclusion that was
possible – that astronomers, in the words of the song, ‘don’t know much
about biology’. Tryptophan was shot out of the sky only because an alert
astronomer was sufficiently familiar with an instrument and its foibles to
see at once that a mistake had been made. I doubt whether more than a
handful of those present would have spotted it – most astronomers are too
specialised to be familiar with the nuts and bolts of the many
subspecialisms of their science.

And that is the crux of the problem. Hardly a corner of science is untouched
by this great synthesis; evidence is plucked from here and there in a manner
uncomfortably reminiscent of Erich von Danniken. The argument as presented
appears plausible, but we are being offered a highly selective
interpretation of an exceedingly diverse mass of data. Who can examine it
for gaffes, unfavourable evidence withheld, alternative explanations not
offered? Are there any more tryptophans? I cannot say. To do that I would
not only have to be an astrophysicist, a cosmochemist, a molecular
biologist, a biochemist, a virologist, a bacteriologist, an evolutionary
biologist, a geneticist, an epidemiologist, a meteorologist and a
palaeontologist, but also have an intimate knowledge of numerous fields
within those disciplines. (It is a failing I share with the authors, so I do
not feel disqualified from writing this review.)

But I can say this. In spite of their many invectives against biologists for
failing to explain the ultimate origin of life, Hoyle and Wickramasinghe
notably fail to do it themselves – moving the problem from a little warm
pond on Earth to a big cold cloud in space is not much of an advance. They
offer nothing to compare with, for example, Richard Dawking’s carefully
argued scenario for the development of self-replicating molecules in The
Selfish Gene.

So what can we conclude? As a sceptical scientist I despair of this
controversy being resolved in the lifetime of the protagonists. As this book
amply shows, an intriguing idea has now been elevated to a personal crusade
against the ‘pre-Copernican’ establishment. The authors rage against the
very people whose help they need to develop their ideas, and put them to the
test. That said, the notion of universal life has a sweeping grandeur. It is
exciting, exuberant, it sets the pulse racing, the imagination soaring. So
immense are the implications that even biologists, so foolishly denigrated
in this book, might take time to ponder whether an influx of carbon-based
molecules from space – which undoubtedly are out there – might have had
some part to play in the origin and evolution of life on Earth.

Tony Jones is a science writer.